Fuel cell stack voltage detection device

Abstract

The utility model provides a fuel cell stack voltage detection device which comprises an inspection fixed plate (2-1), and a plurality of voltage electricity taking modules (2-2) are arranged on the inspection fixed plate (2-1); the voltage electricity taking module (2-2) comprises a probe (3-4), a probe fixing plate (3-1), a circuit fixing plate (3-2), a circuit board (3-3) and a wiring terminal (3-6); one end of the probe (3-4) is arranged in the probe fixing plate (3-1), and the other end of the probe (3-4) is inserted into the side surface of a bipolar plate (4-3) in the electric pile to take electricity; the probe (3-4) is electrically connected with the circuit board (3-3), the wiring terminal (3-6) is arranged on the circuit board (3-3), and the wiring terminal (3-6) transmits current from the circuit board (3-3) to a controller through an electric wire. According to the technical scheme, a grouping type structure is adopted for routing inspection, and the problem of routing inspection probe deviation caused by length difference between different electric piles is solved.

Description

Technical Field

[0001] This utility model relates to the field of fuel cell stack voltage detection technology, and in particular to a fuel cell stack voltage detection device. Background Technology

[0002] The fuel cell stack is the core component of a fuel cell system, consisting of hundreds of individual cells stacked in series. During fuel cell power generation, due to internal flow channel issues, the flow rates of hydrogen and oxygen through each individual cell are inconsistent, resulting in varying voltages for each cell. Since the stack is composed of cells connected in series, the overall performance of the stack depends on the worst-performing individual cell. Therefore, accurately collecting voltage data from each individual cell and monitoring their voltage status in real time is essential. Fuel cell inspection systems, as devices for collecting and detecting individual cell voltage data, have significant practical value.

[0003] There are three main methods in existing voltage acquisition devices. The first method involves welding the inspection harness to the bipolar plate of the fuel cell stack to acquire the voltage signal. This method is prone to welding errors during production. If a welding error occurs, it needs to be desoldered and re-welded, and sometimes operational errors can even damage the bipolar plate. Moreover, during operation, the solder joints are prone to falling off, making maintenance very inconvenient. Furthermore, since graphite bipolar plates cannot be welded to the harness and can only be glued, this problem is exacerbated.

[0004] The second approach involves designing and manufacturing a matching bipolar plate and inspection module. A protruding anti-detachment clip is designed on the edge of the bipolar plate, and the inspection module internally clamps the anti-detachment clip on the bipolar plate using clamping terminals, with an external insulating plastic shell. This method offers convenient insertion and removal and good shock resistance, but its production cost is extremely high, and it is not compatible with graphite bipolar plates.

[0005] The third type uses a barbed metal probe with a groove pre-drilled in the bipolar plate, into which a slender probe is inserted. While this method is easy to install, it is difficult to disassemble, and the bipolar plate is easily damaged when pulled out. Furthermore, the probe is slender and unrestrained, resulting in poor vibration resistance.

[0006] In conclusion, the existing inspection solutions are not good enough in terms of economy and applicability. Utility Model Content

[0007] In view of this, the purpose of this utility model is to provide a fuel cell stack voltage detection device. The inspection adopts a group structure, which solves the problem of inspection probe deviation caused by the difference in length between different stacks.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: a fuel cell stack voltage detection device, comprising an inspection fixing plate (2-1), on which multiple voltage power extraction modules (2-2) are provided; the inspection fixing plate (2-1) is fixed on both sides of the fuel cell stack (1-2); the voltage power extraction module (2-2) includes a probe (3-4), a probe fixing plate (3-1), a circuit fixing plate (3-2), a circuit board (3-3), and a terminal block (3-6); one end of the probe (3-4) is disposed inside the probe fixing plate (3-1), and the other end of the probe (3-4) is inserted into the side of the bipolar plate (4-3) in the fuel cell stack for power extraction; the probe (3-4) is electrically connected to the circuit board (3-3), and the terminal block (3-6) is provided on the circuit board (3-3), and the terminal block (3-6) transmits current from the circuit board (3-3) to the controller through a wire.

[0009] In a preferred embodiment, the probe (3-4) is provided with a head and a tail; the head of the probe (3-4) is inserted into the side contact of the bipolar plate (4-3).

[0010] In a preferred embodiment, the probe (3-4) is provided with an internal spring (4-2) so that there is an elastic space between the head of the probe (3-4) and the side insertion point of the bipolar plate (4-3).

[0011] In a preferred embodiment, a spring (4-1) is provided between the tail of the probe (3-4) and the circuit board (3-3).

[0012] In a preferred embodiment, the circuit mounting plate (3-2) is made of insulating material.

[0013] In a preferred embodiment, the probe fixing plate (3-1) is made of insulating material.

[0014] In a preferred embodiment, the controller is specifically a CVM controller.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. Utilize the exposed bipolar plate side end face of the fuel cell stack without altering the fuel cell stack's main structure;

[0017] 2. The structure is compact and does not increase the maximum boundary size of the fuel cell stack, which facilitates fuel cell stack packaging;

[0018] 3. The finished product is aesthetically pleasing, has a simple structure, is easy to install and maintain, and is more economical. It is suitable not only for the trial production of fuel cell stack samples but also for mass production.

[0019] 4. Taking into full account the possible vibrations and changes in ambient temperature during the transfer and operation of the fuel cell stack, we ensured good contact of the inspection sampling probe and guaranteed the reliability of the voltage sampling probe.

[0020] 5. Low cost, strong applicability, and solves the problem of difficult voltage sampling of graphite fuel cells;

[0021] 6. Ensure the impedance consistency of each voltage sampling device to improve the accuracy of voltage sampling during inspection;

[0022] 7. The inspection adopts a group structure, which solves the problem of inspection probe deviation caused by the difference in length between different fuel cells. Attached Figure Description

[0023] Figure 1 This is an isometric view of the inspection sampling device (charge pile);

[0024] Figure 2 This is a front view of the inspection sampling device (without a fuel cell).

[0025] Figure 3 Three-view diagram of the inspection fixing plate;

[0026] Figure 4 The main view and left view of a single inspection module;

[0027] Figure 5 This is a partial cross-sectional view of a single inspection module;

[0028] Figure 6 This is the circuit board schematic.

[0029] The annotations in the attached figures are explained as follows:

[0030] 1-1 Voltage sampling device, 1-2 fuel cell stack, 1-3 fuel cell stack manifold;

[0031] 2-1 Inspection and fixing plate, 2-2 Voltage power supply module;

[0032] 3-1 Probe mounting plate, 3-2 Circuit board mounting plate, 3-3 Circuit board, 3-4 Probe, 3-5 Screw, 3-6 Terminal block;

[0033] 4-1 Spring, 4-2 Internal Spring, 4-3 Bipolar Plate. Detailed Implementation

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0036] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application; as used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise; furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0037] A fuel cell stack voltage detection device 1-1, reference Figures 1-6 It includes an inspection fixing plate 2-1, on which multiple voltage power taking modules 2-2 are provided. The multiple voltage power taking modules 2-2 are used to perform power taking and detection on the sides of multiple bipolar plates 4-3. This grouped structure solves the problem of inspection probe deviation caused by the difference in length between different stacks 1-2.

[0038] The inspection fixing plate 2-1 is fixed on both sides of the fuel cell stack 1-2; the fuel cell stack 1-2 is also connected to the fuel cell stack manifold 1-3; by utilizing the exposed side end faces of the bipolar plates 4-3 of the fuel cell stack 1-2, the main structure of the fuel cell stack 1-2 is not changed, the structure is compact, and the maximum boundary size of the fuel cell stack 1-2 is basically not increased, which facilitates the encapsulation of the fuel cell stack 1-2. The voltage detection device is installed on both sides of the fuel cell stack. The probe in the voltage detection device takes power from the side of the bipolar plate 4-3, between the frames of the two membrane electrodes 4-4. Due to the presence of the frames of the membrane electrodes 4-4, the two bipolar plates 4-3 are physically separated, which not only prevents the probe from contacting other bipolar plates, but also allows clear observation of whether the inspection probe accurately contacts the bipolar plate to be tested.

[0039] Specifically, the voltage power extraction module 2-2 includes a probe 3-4, a probe fixing plate 3-1, a circuit fixing plate 3-2, a circuit board 3-3, a screw 3-5, and a terminal block 3-6. One end of the probe 3-4 is located inside the probe fixing plate 3-1, and the other end of the probe 3-4 is inserted into the side of the bipolar plate 4-3 in the fuel cell stack to extract power. The probe 3-4 is electrically connected to the circuit board 3-3, and the circuit board 3-3 is provided with the terminal block 3-6. The terminal block 3-6 transmits current from the circuit board 3-3 to the controller through a wire.

[0040] The probe 3-4 is provided with a head and a tail; the head of the probe 3-4 is inserted into the side connector of the bipolar plate 4-3. An internal spring 4-2 is provided inside the probe 3-4, creating an elastic space between the head of the probe 3-4 and the side connector of the bipolar plate 4-3. A spring 4-1 is provided between the tail of the probe 3-4 and the circuit board 3-3.

[0041] Specifically, probe 3-4 is made of conductive material and contains an internal spring 4-2, allowing the probe head to be compressed. To ensure the pressure between the spring head 3-4 and the side of the bipolar plate 4-3 reaches a threshold, according to F=k·x, the spring constant k is determined by the spring's physical properties. The spring compression x is equal to the relative position of the probe fixing plate 3-1 and the side of the bipolar plate 4-3. Therefore, the relative position of the probe fixing plate 3-1 and the side of the bipolar plate 4-3 determines the pressure magnitude. A reasonable compression level ensures good contact for probe 3-4. However, the compression of probe 3-4 is not constant. When the fuel cell stack 1-2 operates, its temperature rises, causing thermal expansion and contraction, increasing the compression of the internal spring 4-2. Therefore, in designing the probe 3-4 structure, the length of the internal cavity is made shorter than the initial length of the internal spring 4-2. Thus, after the probe is encapsulated, a certain pre-compression exists. Therefore, when selecting the internal spring 4-2, a spring with a smaller spring constant can be chosen. Therefore, the elastic force will not change excessively when the compression of probe 3-4 changes. Furthermore, two sampling probes 3-4 are provided on each electrode to ensure the reliability of voltage sampling. Simultaneously, the two probes 3-4 on the same bipolar plate 4-3 are not on the same vertical line, further preventing the situation where neither probe 3-4 is in contact with the bipolar plate 4-3. The tail of probe 3-4 is not rigidly connected to circuit board 3-3, but is connected by a spring 4-1. The preload of spring 4-1 applies a certain pressure to probe 3-4, ensuring that probe 3-4 will not be displaced due to the reaction force of the internal spring 4-2, thus preventing measurement deviation; at the same time, the detection current is conducted from probe 3-4 to circuit board 3-3.

[0042] Specifically, the circuit mounting plate 3-2 and the probe mounting plate 3-1 are both made of insulating material. The electrical insulation between adjacent probes 3-4 is good, preventing power supply disruption due to insulation failure of adjacent probes 3-4 under special circumstances.

[0043] Specifically, the controller is a CVM controller. Terminals 3-6 are soldered onto circuit board 3-3, and current is transmitted from circuit board 3-3 to the CVM controller via wires.

[0044] Due to factors such as the packaging of fuel cell stacks 1-2, there may be slight errors in the spacing of bipolar plates 4-3 between different fuel cell stacks of the same model. After stacking dozens or hundreds of bipolar plates, this error can reach the millimeter level. Therefore, by grouping probes 3-4, this error can be eliminated between voltage sampling modules 2-2 in each group.

Claims

1. A fuel cell stack voltage detection device, characterized in that, The device includes an inspection mounting plate (2-1), on which multiple voltage extraction modules (2-2) are mounted. The inspection mounting plate (2-1) is fixed to both sides of the fuel cell stack (1-2). Each voltage extraction module (2-2) includes a probe (3-4), a probe mounting plate (3-1), a circuit mounting plate (3-2), a circuit board (3-3), and a terminal block (3-6). One end of the probe (3-4) is located inside the probe mounting plate (3-1), and the other end of the probe (3-4) is inserted into the side of the bipolar plate (4-3) in the fuel cell stack to extract power. The probe (3-4) is electrically connected to the circuit board (3-3), and the terminal block (3-6) is mounted on the circuit board (3-3). The terminal block (3-6) transmits current from the circuit board (3-3) to the controller via wires.

2. The fuel cell stack voltage detection device according to claim 1, characterized in that, The probe (3-4) is provided with a head and a tail; the head of the probe (3-4) is inserted into the side connector of the bipolar plate (4-3).

3. The fuel cell stack voltage detection device according to claim 2, characterized in that, An internal spring (4-2) is provided inside the probe (3-4), so that there is an elastic space between the head of the probe (3-4) and the side insertion point of the bipolar plate (4-3).

4. The fuel cell stack voltage detection device according to claim 2, characterized in that, A spring (4-1) is provided between the tail of the probe (3-4) and the circuit board (3-3).

5. The fuel cell stack voltage detection device according to claim 1, characterized in that, The circuit mounting plate (3-2) is made of insulating material.

6. The fuel cell stack voltage detection device according to claim 1, characterized in that, The probe fixing plate (3-1) is made of insulating material.

7. The fuel cell stack voltage detection device according to claim 1, characterized in that, The controller is specifically a CVM controller.

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